Perivascular versus nonperivascular small HCC treated with percutaneous RF ablation: Retrospective comparison of long-term therapeutic outcomes

Purpose: To compare the long-term therapeutic outcomes of radiofrequency (RF) ablation for small perivascular hepatocellular carcinoma (HCC) and nonperivascular HCC. Materials and Methods: This retrospective study was approved by the institutional review board. Between December 2004 and April 2008, 241 patients (175 men and 66 women; age range, 32-82 years) with a single early-stage HCC that was 3 cm or smaller in the greatest dimension underwent ultrasonography- guided percutaneous RF ablation as a first-line treatment. The patients were divided into two groups according to the presence or absence of contacting hepatic vessels that were 3 mm or larger in axial diameter: a group with perivascular HCC (n = 58) and a group with nonperivascular HCC (n = 183). Cumulative local tumor progression, disease-free and long-term survival rates, and prognostic factors were assessed by using Cox proportional hazard models with Bonferroni correction. Results: The overall median follow-up period was 58 months (range, 13-92 months). The cumulative local tumor progression rates were 10%, 16%, and 26% at 1, 3, and 5 years, respectively, in the perivascular group, and 6.7%, 15.5%, and 20.5% in the nonperivascular group; the differences were not significant (P = .323). The corresponding disease-free survival rates were 79%, 41%, and 29% in the perivascular group and 71.3%, 38.7%, and 26.0% in the nonperivascular group, with no significant difference (P = .689). The corresponding overall survival rates were 100%, 94%, and 82% in the perivascular group and 100%, 88.4%, and 73.9% in the nonperivascular group, also without significant difference (P = .267). There was no significant prognostic factor for local tumor progression, whereas extrahepatic and intrahepatic distant recurrences were significant prognostic factors for overall survival in multivariable analysis. Conclusion: The long-term therapeutic outcomes of RF ablation as first-line treatment for small perivascular HCC were similar to those for nonperivascular HCC.